There are many examples of height adjustable tables for use in association with a work station. Computer stations are, perhaps, the best examples of work surfaces which are height-adjustable and can include either a mechanical counter-balancing arrangement, electrical drive arrangements or hydraulic arrangements for controlling the height of the work surface. There are also many telescopic legs for providing variable heights. The present invention provides a simple mechanical arrangement for varying the height of a work surface, such as a table or mobile table, which is relatively inexpensive to use, and provides increased stability as the height of the table increases.